The Virology Core will have several functions that will be critical for success of this PO1 Grant. It will grow and titer wild type SARS-CoV and HCoV-OC43. It will develop recombinant SARS-CoV, HCoV-OC43, MHV, adenovirus, influenza A and respiratory syncytial virus. These viruses will be used by all investigators in the Program, both at the University of Iowa and Loyola University Medical Center, to probe factors involved in SARS-CoV pathogenesis. The Core will teach members of the Project the methods important for recombinant virus production, as well as provide a service function. Personnel working in the Core are experienced in virological and cell culture techniques and have also been trained to work in our BSL3 laboratory, since it will be necessary to propagate some of the recombinant viruses under these more stringent conditions. The Core will efficiently provide reagents for the Program investigators, thereby allowing them to focus on issues related to the pathogenesis of SARS-CoV.